Sodium hydride → 1-(4-methanesulfonyl-benzyl)-3-nitro-1H-pyrazole

HRID 546012Notes

Reaction equation

HRID 546012 reaction equation
[N+:1]([C:4]1[CH:8]=[CH:7][NH:6][N:5]=1)([O-:3])=[O:2].[H-].[Na+].Br[CH2:12][C:13]1[CH:18]=[CH:17][C:16]([S:19]([CH3:22])(=[O:21])=[O:20])=[CH:15][CH:14]=1>CN(C)C=O>[CH3:22][S:19]([C:16]1[CH:17]=[CH:18][C:13]([CH2:12][N:6]2[CH:7]=[CH:8][C:4]([N+:1]([O-:3])=[O:2])=[N:5]2)=[CH:14][CH:15]=1)(=[O:20])=[O:21]

Participants

5

Reactant 3

HCID 24758Sodium hydrideHCID 27335814-(Methylsulfonyl)benzyl BromideHCID 178526745HCID 178526745, compound

Product 1

HCID 671917621-(4-methanesulfonyl-benzyl)-3-nitro-1H-pyrazoleYield 55.3%

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

To a solution of 3-nitro-1H-pyrazole (prepared in example 3, 150 mg, 1.33 mmol) in anhydrous N,N-dimethylformamide (2 mL), a 60% dispersion of sodium hydride in mineral oil (58 mg, 1.46 mmol) was added while stirring under nitrogen. After the effervescence ceased and the mixture was stirred for additional 30 min, 1-bromomethyl-4-methanesulfonyl-benzene (364 mg, 1.46 mmol) was added. The mixture was continued to stir under nitrogen for an additional 2 h. The solvent was removed in vacuo and purification by ISCO flash column chromatography (Teledyne Isco RediSep Flash Column 40 g; 0% ethyl acetate/hexanes to 50% ethyl acetate/hexanes) afforded 1-(4-methanesulfonyl-benzyl)-3-nitro-1H-pyrazole (207 mg, 55%) as a white solid.

Workup

  1. stirringthe mixture was stirred for additional 30 min
  2. stirringto stir under nitrogen for an additional 2 h
  3. customThe solvent was removed in vacuo and purification by ISCO flash column chromatography (Teledyne Isco RediSep Flash Column 40 g; 0% ethyl acetate/hexanes to 50% ethyl acetate/hexanes)

Sources & evidence

ORD record
ord-d70d0a0c061f4c48b8196fd61820a096
Source dataset
uspto-grants-2011_05
Patent number
US07935699B2

Reaction notes

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